I picture might help. But really, don't worry about this nonsense in high school.
High school is way too goofy. For one, guys don't know what they want while in high school. All they know is that they want to be cool, but they don't want to try stuff. It takes one person falling on their proverbial face, and then the rest follow like lemmings.
Get what I mean?
So don't be concerned with not being asked out, truth be told you are probably avoiding a lot of garbage that some of us would have been better off avoiding back then.
And you are pretty, and there is a right guy for you out there. For sure, mark my words. You just keep walking tall, and not paying attention to the bull butter getting sprayed up and down the hallways.
You can get all the people in the world to tell you you are pretty and you would probably still be unhappy. The truth you have to look inside yourself to find your true happiness. I do understand that you may think you have some flaws but who doesn't think that! No one is perfect and you should accept what you have if that the problem. Besides you can help yourself feel better by choosing a part of you body (ex. I love my arms they are cute---even if your arms are flabie, who cares), stand in front of a mirror a say to yourself "I AM BEAUTIFUL, BECAUSE I AM ME" You know your looks don't matter and if you feel that your personality isn't what you would like it to be, you can work on it. Try new hobbies, go out there and try things that make you happy, like a club at school, sports, art, music, etc. not drugs! you may even find someone. You probably are a beautiful girl, look around, what woman isn't, sometimes it just takes some time to see that.